Plastic enclosures are ubiquitous in virtually all of today's electrical and electronic equipment (EEE). Although plastics can be readily injection molded into intricate, thin-walled structures, they also must meet important fire safety standards. Components in high-powered computers are highly concentrated heat sources that may result in rapid overheating and runaway thermal events. Electrical and electronic products are also subject to fire risks from electrical short circuits that can cause ignition within a product. Without the use of flame-retardants to mitigate ignition resistance, the potential for fire danger increases as the number of electronic products—and cables, wires and electronic chargers to power them—increases in households, offices and commercial buildings.
Examples of flame-retardants are phosphazenes and polyphosphazenes. Incorporating flame-retardants into the materials used in electrical and electronic components enables manufacturers to meet fire safety standards (Such as UL 94, Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances), while also ensuring a product meets key technical requirements such as weight, durability, flexibility, and impact resistance. As new and more sophisticated material technologies emerge, and requirements for fire resistant materials evolve, the flame-retardant itself must keep pace. Flame-retardant manufacturers will continue to innovate and develop effective and sustainable flame-retardants that meet new product demands for fire resistance, high performance and cost-effectiveness, and address environmental health and safety concerns.
Formulating plastic materials which meet not only flammability requirements, but key performance metrics (such as impact resistance), is an area of current research focus. Plastic manufacturers will often blend small molecule flame-retardants into the base thermoplastic to render it ignition resistant. However, there is always a trade off in physical properties. That is, by increasing the loading level of the flame-retardant (FR) to achieve a specific UL 94 rating, impact resistance is often degraded.
Moreover, plastics are typically derived from a finite and dwindling supply of petrochemicals, resulting in price fluctuations and supply chain instability. Replacing non-renewable petroleum-based polymers with polymers derived from renewable resources may be desirable. However, there may be limited alternatives to petroleum-based polymers in certain contexts. To illustrate, particular plastics performance standards may be specified by a standards body or by a regulatory agency. In some cases, alternatives to petroleum-based polymers may be limited as a result of challenges associated with satisfying particular plastics performance standards.
Thus, there is a need to compensate for degraded impact resistance while maintaining high levels of flame retardancy.